Bottles and other containers may be manufactured by various processes, such as thermoforming, rotomolding, blow molding, or extrusion blow molding. Containers may be produced from single or multi-layer materials. A barrier layer may be included in a multi-layer material to extend the shelf life of food or beverage products to be packaged in a container made therefrom. For example, barrier layers may be used where products to be packaged are sensitive to certain gases, or loss of volatiles, flavors, or aromas.
However, a loss of overall barrier performance often occurs where a gap between the barrier layer exists at the weld or seal areas of containers. Accordingly, there is a need for methods for making containers having improved barrier performance at these seal areas.